Researchers worked out an estimate for the number ofaround the World – and the whole is “significant.”
Scientists at the University of Hong Kong say there are 20,000,000,000,000,000 – that’s 20 quadrillion – of the critters around the globe. The combined weight of those ants is greater than all the wild birds and mammals on the planet.
The weight is also equivalent to about one-fifth of the total weight of humans. Scientists say the results, published Monday in the peer-reviewed Proceedings of the National Academy of Sciences, are “conservative.”
Ants are in almost every ecosystem around the planet, thanks to their highly social nature. At the moment, there are more than 15,700 named species and subspecies, but there are many more that have not been named yet.
To arrive at the total, researchers analyzed 489 studies from around the world, covering every continent and major habitat. Other scientists were tasked with directly observing and counting ants using traps and leaf samples – and then their research was combined to arrive at the 20,000,000,000,000,000 estimate.
Scientists say that is between two and 20 times higher than previous estimates.
Researchers also wanted to work out the total weight of all the ants. They produced an estimated “biomass” of about 12 million tonnes of carbon. But carbon only makes up about half of the ant’s dry weight – meaning the total mass is likely to be even higher.
Researchers discovered that ants are not evenly distributed across the planet; instead, they peak in the tropics, emphasizing the importance of those regions as climate changes. They were also abundant in both forests and arid regions.
Of course, all these ants play a vital role in our ecosystems. The insects aerate the soil, disperse seeds, break down organic matter and create habitats for other animals. They are also an important part of the food chain, according to the scientists, and can be more effective than pesticides for farmers.
Several animal species cannot survive without ants, including some birds, which depend on them for prey, and numerous plant species that feed or provide habitat for the insects in exchange for protection or seed dispersal.
But they are under serious threat, due to habitat destruction and fragmentation, the use of chemicals, invasive species and climate change.
“It is in the interest of humanity to monitor ant populations,” say scientists. “Counting ants is not difficult, and citizen scientists from all over the world could help investigate how these important animals are coping during major environmental changes.”
The scientists acknowledged that there were some limitations to the results, however. The sites from their samples were not evenly distributed in terms of geographic regions, and most were collected from the ground, leaving much to be learned about populations in trees or underground.
But researchers still hope that these findings can provide a vital baseline from which to monitor ant populations in the future, amid environmental changes.
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Puerto Rico remains in the dark, there is no clean water after Hurricane Fiona made landfall